It is commonly noted that unauthorized trademarks and barcodes are used on counterfeit products. Unauthorized use of a registered trademark will be subject to civil and/or criminal liabilities in violation of the Trademark Act. However, it is an issue whether unauthorized use of a barcode will violate any laws or regulations.

A commodity barcode is comprised of a country code, a company code and a code of specific commodities, and is issued by GS1 or an authorized administrative authority (the competent authority in Taiwan is GS1 Taiwan). In the past, most courts held that forgery of a barcode or use of a forged barcode did not constitute an offence on the ground that general consumers would not select commodities on the basis of a barcode.

However, the Criminal Judgment in 2010 of the Taipei District Court on a criminal case held that once a commodity barcode is read through a computer, what the commodity is and its manufacturer and country of manufacture can be immediately identified. Therefore, a barcode is equivalent to a trade name. As a commodity barcode is a symbol applied on articles and can serve as proof in business practice or a contract, it is deemed a quasi-private document. Thus, the defendant's asking a third party to forge the barcode and use the same is deemed an act of producing a quasi-private document in the name of another party.

The court also pointed out that it is a common known fact that a commodity barcode is a symbol of the automated administration of a series of processes for general products including manufacturing, wholesale and sale. Moreover, the defendant was aware that a barcode was used to identify the owner, manufacturer, seller or importer of commodities. As the defendant and the legitimate user of the barcode in that case had no connection at all, the printing of such barcode on the defendant's commodities made others misidentify the user of the barcode as the owner, manufacturer, seller or importer of these commodities, which affected the administration of the barcode by GS1 Taiwan or other barcode administrative authorities and also impaired the legitimate user's management of the commodities with the barcode.

Recently the Supreme Court, the Intellectual Property Court as well as most of the district courts or other high courts reviewing relevant issues take the same view that unauthorized used barcode should constitute forgery under the Criminal Code.